Has anyone worked with cancelling noise with a high quality speaker instead
of headphones?

I need to eliminate noise from a power substation and the operation
concluded they would not correct the problem.

The noise is mainly 60 Hz and harmonics and level is less than 70 dB.

Phil

This type of science is very complex, and almost impossible to do in a non
controlled laboratory environment. When you move around in the environment,
the levels and phase will shift in relation to your location. This would
have to be very precisely tracked and controlled by some means. The counter
waveform would have to be exactly like the source waveform, with no
distortion difference. A simple pair of speakers and amplifier would never
achieve this very easily. Low frequency sounds are difficult to attenuate
in structures, because of their characteristics.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================


"Audiophil" wrote in message
...
Has anyone worked with cancelling noise with a high quality speaker instead
of headphones?

I need to eliminate noise from a power substation and the operation
concluded they would not correct the problem.

The noise is mainly 60 Hz and harmonics and level is less than 70 dB.

Phil

This type of science is very complex, and almost impossible to do in a non
controlled laboratory environment. When you move around in the environment,
the levels and phase will shift in relation to your location. This would
have to be very precisely tracked and controlled by some means. The counter
waveform would have to be exactly like the source waveform, with no
distortion difference. A simple pair of speakers and amplifier would never
achieve this very easily. Low frequency sounds are difficult to attenuate
in structures, because of their characteristics.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================


"Audiophil" wrote in message
...
Has anyone worked with cancelling noise with a high quality speaker instead
of headphones?

I need to eliminate noise from a power substation and the operation
concluded they would not correct the problem.

The noise is mainly 60 Hz and harmonics and level is less than 70 dB.

Phil

This type of science is very complex, and almost impossible to do in a non
controlled laboratory environment. When you move around in the environment,
the levels and phase will shift in relation to your location. This would
have to be very precisely tracked and controlled by some means. The counter
waveform would have to be exactly like the source waveform, with no
distortion difference. A simple pair of speakers and amplifier would never
achieve this very easily. Low frequency sounds are difficult to attenuate
in structures, because of their characteristics.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================


"Audiophil" wrote in message
...
Has anyone worked with cancelling noise with a high quality speaker instead
of headphones?

I need to eliminate noise from a power substation and the operation
concluded they would not correct the problem.

The noise is mainly 60 Hz and harmonics and level is less than 70 dB.

Phil

This type of science is very complex, and almost impossible to do in a non
controlled laboratory environment. When you move around in the environment,
the levels and phase will shift in relation to your location. This would
have to be very precisely tracked and controlled by some means. The counter
waveform would have to be exactly like the source waveform, with no
distortion difference. A simple pair of speakers and amplifier would never
achieve this very easily. Low frequency sounds are difficult to attenuate
in structures, because of their characteristics.

--

Greetings,

Jerry Greenberg GLG Technologies GLG
=========================================
WebPage http://www.zoom-one.com
Electronics http://www.zoom-one.com/electron.htm
=========================================


"Audiophil" wrote in message
...
Has anyone worked with cancelling noise with a high quality speaker instead
of headphones?

I need to eliminate noise from a power substation and the operation
concluded they would not correct the problem.

The noise is mainly 60 Hz and harmonics and level is less than 70 dB.

Phil

"Jerry G." wrote in


This type of science is very complex, and almost impossible to do in a
non controlled laboratory environment. When you move around in the
environment, the levels and phase will shift in relation to your
location. This would have to be very precisely tracked and controlled
by some means. The counter waveform would have to be exactly like the
source waveform, with no distortion difference. A simple pair of
speakers and amplifier would never achieve this very easily. Low
frequency sounds are difficult to attenuate in structures, because of
their characteristics.

I'll settle for cancellation at a single position ie. when sleeping.
Wavelength for 60 Hz is 340m/60.

If speakers are placed within a meter of the head will this be sufficiently
controlled?

Phil

"Jerry G." wrote in


This type of science is very complex, and almost impossible to do in a
non controlled laboratory environment. When you move around in the
environment, the levels and phase will shift in relation to your
location. This would have to be very precisely tracked and controlled
by some means. The counter waveform would have to be exactly like the
source waveform, with no distortion difference. A simple pair of
speakers and amplifier would never achieve this very easily. Low
frequency sounds are difficult to attenuate in structures, because of
their characteristics.

I'll settle for cancellation at a single position ie. when sleeping.
Wavelength for 60 Hz is 340m/60.

If speakers are placed within a meter of the head will this be sufficiently
controlled?

Phil

"Jerry G." wrote in


This type of science is very complex, and almost impossible to do in a
non controlled laboratory environment. When you move around in the
environment, the levels and phase will shift in relation to your
location. This would have to be very precisely tracked and controlled
by some means. The counter waveform would have to be exactly like the
source waveform, with no distortion difference. A simple pair of
speakers and amplifier would never achieve this very easily. Low
frequency sounds are difficult to attenuate in structures, because of
their characteristics.

I'll settle for cancellation at a single position ie. when sleeping.
Wavelength for 60 Hz is 340m/60.

If speakers are placed within a meter of the head will this be sufficiently
controlled?

Phil

"Jerry G." wrote in


This type of science is very complex, and almost impossible to do in a
non controlled laboratory environment. When you move around in the
environment, the levels and phase will shift in relation to your
location. This would have to be very precisely tracked and controlled
by some means. The counter waveform would have to be exactly like the
source waveform, with no distortion difference. A simple pair of
speakers and amplifier would never achieve this very easily. Low
frequency sounds are difficult to attenuate in structures, because of
their characteristics.

I'll settle for cancellation at a single position ie. when sleeping.
Wavelength for 60 Hz is 340m/60.

If speakers are placed within a meter of the head will this be sufficiently
controlled?

Phil

Audiophil wrote in message ...
---snip---
I'll settle for cancellation at a single position ie. when sleeping.
Wavelength for 60 Hz is 340m/60.


I'm almost afraid to ask, but just how close are you to this power station?

Audiophil wrote in message ...
---snip---
I'll settle for cancellation at a single position ie. when sleeping.
Wavelength for 60 Hz is 340m/60.


I'm almost afraid to ask, but just how close are you to this power station?

Audiophil wrote in message ...
---snip---
I'll settle for cancellation at a single position ie. when sleeping.
Wavelength for 60 Hz is 340m/60.


I'm almost afraid to ask, but just how close are you to this power station?

Audiophil wrote in message ...
---snip---
I'll settle for cancellation at a single position ie. when sleeping.
Wavelength for 60 Hz is 340m/60.


I'm almost afraid to ask, but just how close are you to this power station?

(unitron) wrote in
om:

Audiophil wrote in message
... ---snip---
I'll settle for cancellation at a single position ie. when sleeping.
Wavelength for 60 Hz is 340m/60.


I'm almost afraid to ask, but just how close are you to this power
station?


It takes up two blocks and I am within 100 ft of the nearest components. It
should be possible since computer fans are being muffled by active
cancellation with external speakers as posted on slashdot.org recently.

(unitron) wrote in
om:

Audiophil wrote in message
... ---snip---
I'll settle for cancellation at a single position ie. when sleeping.
Wavelength for 60 Hz is 340m/60.


I'm almost afraid to ask, but just how close are you to this power
station?


It takes up two blocks and I am within 100 ft of the nearest components. It
should be possible since computer fans are being muffled by active
cancellation with external speakers as posted on slashdot.org recently.

(unitron) wrote in
om:

Audiophil wrote in message
... ---snip---
I'll settle for cancellation at a single position ie. when sleeping.
Wavelength for 60 Hz is 340m/60.


I'm almost afraid to ask, but just how close are you to this power
station?


It takes up two blocks and I am within 100 ft of the nearest components. It
should be possible since computer fans are being muffled by active
cancellation with external speakers as posted on slashdot.org recently.

(unitron) wrote in
om:

Audiophil wrote in message
... ---snip---
I'll settle for cancellation at a single position ie. when sleeping.
Wavelength for 60 Hz is 340m/60.


I'm almost afraid to ask, but just how close are you to this power
station?


It takes up two blocks and I am within 100 ft of the nearest components. It
should be possible since computer fans are being muffled by active
cancellation with external speakers as posted on slashdot.org recently.